208 



luxuriant growth of our common Equisetum under practi- 

 cally tropical conditions. Liquid mud under foot and a 

 temperature over ioo° F., and no ventilation. Cavdamine 

 hirsntum is another weed which projects its seeds 3 feet 

 in all directions. Under tropical conditions this plant 

 occupies ten days from birth to maturity, and can reproduce 

 itself a hundredfold every ten days. 



Sagina pvocumbens is a bad weed in the open ground, and 

 there are several others, but I think I have mentioned the 

 most troublesome. 



LASTREA MONTANA FORMOSA-CRISTATA. 



(F.W.S.) 

 The history of this Fern, which formed the frontispiece 

 of the June Gazette, was not correctly given in that 

 number, doubtless owing to my failure to supply the par- 

 ticulars in time for publication. It originated as a seedling 

 from spores of L. montana phimosa-cristata sent to me by 

 Mr. Whitwell, who was himself the raiser of the very 

 beautiful parent. The ancestry of the latter is not cer- 

 tainly known, but from its appearance I should say it was 

 the result of a cross between L. montana covonans of Barnes- 

 and one of the plumose varieties, probably either Mr. 

 Whitwell's own or Mr. Barnes's find. The grandchild, 

 the subject of this paragraph, was the only montana which 

 appeared from the sowing of flumosa-cristata. It differs 

 from its immediate parent in being much more densely 

 crested, and was named from its striking similarity to 

 Athyvium f.f. formosa-cristatum. The plant has had a 

 somewhat chequered career, inasmuch as, three years ago, 

 I divided it into three, intending to send the first division 

 to the giver of the spores. Unfortunately the two best 

 pieces died almost immediately, and it was not until the 

 autumn of 19 16 that I was able again to divide the 

 survivor. The better of these two pieces was sent to 



